After her husband's warning me that the bare mention of the tragedy excited her I had naturally taken great pains to avoid all reference to the subject. I was, consequently, a good deal surprised to hear her broach it with such apparent calmness. I glanced inquiringly at Atkins. "Yes, do," he urged, still looking at his wife. "I'm afraid there isn't much more to tell," I hesitatingly replied; "I gave the newspapers a pretty straight account of the whole affair." "Oh, but you were much too modest," she cried; "a little bird has told us that you are a great detective, and suspected Argot from the first. Say, how did you manage to hit on him? We want all the details, you know." It was her flattery, I am afraid, which loosened my tongue and made me forget my former caution. "Well, it was mostly luck," I assured her, and then proceeded to give a long account of the whole affair. "And now," I said, warming to my topic under their evident interest, "I wonder if either of you, when you read over the description of the murdered man, or when you saw him, for the matter of that, noticed anything peculiar about him? I confess that it escaped me and my attention had to be called to it by Mr. Merritt." "Something peculiar," she repeated. "What kind of a peculiarity do you mean?" "Well, the lack of an important article of apparel," I replied. "No; I didn't notice anything out of the way," she answered, after considering the question for some minutes. I turned towards her husband. He was leaning forward, so deeply absorbed in watching his wife as to be entirely unconscious of my presence, and on his ingenious countenance I was shocked to observe suspicion and love struggling for mastery. Struck by his silence, she, too, looked at him, and as her eyes encountered his I saw a look of fear creep into them, and the faint color fade from her cheeks. When he saw how his behaviour had affected her, he tried to pull himself together, and passed his hand swiftly over his face as if anxious to obliterate whatever might be written there. "Well, what is this missing link?" he asked, with obviously enforced gaiety. He looked squarely at me, and, as he did so, I became convinced that he already knew the answer to that question. For a moment we stared at each other in silence. Were my looks tell-tale, I wondered, and could he see that I had discovered his secret? "Say," broke in Mrs. Atkins, "don't go to sleep. What was this missing thing?" I would have given anything not to have had to answer. "No hat was found with the body," I said. Atkins, I noticed, was again looking fixedly at his wife, who had grown deathly white, and sat staring at him, as if hypnotised. Both had, apparently, forgotten me, but yet I felt deeply embarrassed at being present, and dropped my eyes to my plate so as to give them a chance to regain their composure unobserved.